Salvia (Sage) should be the poster child for the easy, low water requiring perennial. It is one of the best border plants for our semi-arid area and comes in many sizes, colors and growth habits.
I have always wanted to design a garden using predominantly Salvias with a few companion plants like Roses and Lavender. That is how varied these plants are- you could create a whole garden with just Salvia hybrids.
Salvias also have annual forms which are great long term color for hot areas.
The colors tend to be intense i.e. hot pink, red and varied blues. The trumpet shaped flowers are a favorite of hummingbirds and bees providing food for them over at least 6 months.
The one thing you should know about caring for Salvia is that it should be pruned back, usually hard, after blooming or in the winter. You will often see the new growth sprouting from the base so all the woody areas can be trimmed off.
They like some water but can take dry periods between watering quite well. Salvias vary in water needs, sun exposure preference and ability to withstand freeze so check Sunset Western Garden Book for tips and info. Many of my plants that were damaged by freeze came back from the base so it is worth trying the tropical forms where they have some protection i.e. tree
or eave cover.
Oh yeah, Salvia has a culinary form too. You can use the hybrids as an herb but for good flavor use the Sage labeled for use as an herb. Some of the bush forms taste nasty.
Salvias have little trouble from bugs and the deer tend to leave them alone too- yippee.
I put a Salvia blog in this month because they are great fall color- they tend to like the warm, dry months.
Hope you will try growing some and if you have them already that this will encourage you to notice them even more!